Rke: How to loadbalance apiserver across the cluster

I’m performing a 3M/etcd + 3W air-gapped installation using rke 0.2.2.

We have a loadbalancer which we’d like to use to loadbalance all internal api requests between the nodes, from workers to masters for example.

I don’t see anyway of specifying this in cluster.yml.
(I’m looking for something equivalent to kubeadm’s controlPlaneEndpoint).

Any pointers to how to do this would be greatly appreciated, thx.